Jamieson-Fausset-Brown Bible Commentary

Abner sent messengers to David--Though his language implied a secret conviction, that in supporting Ish-bosheth he had been laboring to frustrate the divine purpose of conferring the sovereignty of the kingdom on David, this acknowledgment was no justification either of the measure he was now adopting, or of the motives that prompted it. Nor does it seem possible to uphold the full integrity and honor of David's conduct in entertaining his secret overtures for undermining Ish-bosheth, except we take into account the divine promise of the kingdom, and his belief that the secession of Abner was a means designed by Providence for accomplishing it. The demand for the restoration of his wife Michal was perfectly fair; but David's insisting on it at that particular moment, as an indispensable condition of his entering into any treaty with Abner, seems to have proceeded not so much from a lingering attachment as from an expectation that his possession of her would incline some adherents of the house of Saul to be favorable to his cause.